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arXiv · 1911.09120

Searching for Sterile Neutrino with X-ray Intensity Mapping

A. Caputo·M. Regis·M. Taoso
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Abstract

The cosmological X-ray emission associated to the possible radiative decay of sterile neutrinos is composed by a collection of lines at different energies. For a given mass, each line corresponds to a given redshift. In this work, we cross correlate such line emission with catalogs of galaxies tracing the dark matter distribution at different redshifts. We derive observational prospects by correlating the X-ray sky that will be probed by the eROSITA and Athena missions with current and near future photometric and spectroscopic galaxy surveys. A relevant and unexplored fraction of the parameter space of sterile neutrinos can be probed by this technique.

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A. Caputo, M. Regis, M. Taoso. 2019-11-20. Searching for Sterile Neutrino with X-ray Intensity Mapping. https://doi.org/10.1088/1475-7516%2F2020%2F03%2F001

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